This paper describes the control and reduction of agglomeration of the thin copper seed layer deposited on different barrier layers. Higher stress is applied in layers deposited on TaN and Ta barrier layers. This stress greatly affects the agglomeration and adhesion strength. This stress can be reduced markedly with employing a TaSiN barrier layer instead of Ta barrier layer. Correlations have been found between the stress in as-deposited copper seed layer and the agglomeration height formed with this annealing. That is, agglomeration occurs markedly in the layer on tantalum nitride ͑TaN͒ and Ta barrier layers. Although lower stress layer can be accomplished at the Cu seed/TaSiN interface, no agglomerations occur in the TaSiN barrier layer. This barrier layer for copper diffusion can also get promising barrier performance.

Stress of copper seed employing in the copper interconnection layer is studied. Since this stress affects largely the adhesion strength at the Cu/barrier layers and the Cu͑111͒ orientation of copper layer, reduction of stress is important. Higher and high stresses are applied in the layer on TaN and Ta barrier layers. These layers can lead to poor adhesion strength. Much better adhesion strength can be accomplished in the layer on the TaSiN barrier layer. The surface changes to rough surfaces with annealing at 400°C in the layer deposited on TaN. The highly stressed layer changes to a low stress layer as a result of this agglomeration. However, a smooth surface is held in the low stress layer on the TaSiN barrier layer.

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This paper describes various parameters affecting to the ͑111͒ orientation in electroplating copper conductive layers. Control of this orientation is important because resistivity, stress, adhesion strength, and electromigration resistance of copper layer are affected largely by this orientation. This orientation cannot be controlled with varying electroplating conditions but can be controlled by the orientation of the copper seed layer used as substrate. That is, the ͑111͒ orientation of electroplating copper layer is closely related with that of the seed layer. Orientation of the seed layer is determined mainly by the barrier layer. Weakly and highly ͑111͒ oriented copper layer is obtained when the seed layer is deposited on tantalum nitride and Ta barrier layers, respectively. Still higher orientation is attained in the depositing of copper layer on a TaSiN barrier layer. Agglomeration does not occur with annealing in the highly oriented copper seed layer.